capture.c

本程序实现基于pic16f877的CCP输入捕捉和频率测量功能。

//CCP_C1程序
#include<pic.h>
char flag;
int x,y;

void delay1()
{unsigned int i;
for(i=1000000;i>0;i--);}

void delay2()
{unsigned int i;
for(i=2000000;i>0;i--);}

void display()
{
PORTC=x<<4;
delay2();
PORTC=x&0xF0;
delay1();
PORTC=y<<4;
delay2();
PORTC=y&0xF0;
delay1();
}

void  interrupt CCP1()//
{
if(flag==0)
{CCP1M0=1;TMR1H=TMR1L=0;
flag=1;goto exit;};
{CCP1M0=0;
y=CCPR1H;
x=CCPR1L;
flag=0;
}
exit:CCP1IF=0;}

void main()
{
TRISC=0x04;//rc2口作in口
T1CON=0X31;INTCON=0XC0;
CCP1CON=4;flag=0;
CCP1IE=1;CCP1IF=0;
loop1:
display();
goto loop1;

}